1. Field of the Invention.
The present invention relates to the field of clutch brake assemblies.
2. Prior Art.
For mobile homes, trailers and the like, it is advantageous to have an awning which will provide a shaded and protected area at the side of the vehicle. For this purpose, awning assemblies have been used wherein a horizontal roller is rotatably supported on a shaft by a pair of support arms, the arms being pivotably supported in fore and aft positions adjacent the lower portion of the vehicle. The awning itself has its inner edge attached adjacent the top of the side of the vehicle, with the opposite edge thereof attached to the roller so as to enable the rolling and unrolling of the awning onto and off of the roller. In this manner the awning can be rolled up onto the roller for stowing, which of course will cause the support arms to themselves lie substantially flat against the side of the vehicle. When locked or retained in the rolled up position, the vehicle may be operated at highway speeds without damaging the awning or awning mechanism. In use the awning is simply released and the support arms pulled outward to unroll the awning and support the awning outward from the side of the vehicle.
For convenience in rolling up such an awning assembly, a coil spring may be provided within the roller, coupled in torsion about the axis of the coil spring, so as to provide a self winding action much like a window shade roller spring. In so doing however, one needs some form of relatively positive lock to maintain the awning in the rolled up position, adequate to resist wind forces encountered during transit at highway speeds. On the other hand, when the awning is to be used, such a locking mechanism must be released, it being also desirable to inhibit the tendency of the spring to roll up the awning so that it will not snap back when partially unrolled, and need not be weighted or tied down when fully unrolled. For this purpose, a Locking Device for Roll Up Awnings is shown in U.S. Pat. No. 3,870,096. In that device, a brake is mounted on a lever and within a brake drum, the lever being rotatable between first and second positions and encouraged to either of those two positions by an over center spring. When in either of the two positions, attempted rotation of the drum with respect to the brake in one direction will cause the brake to jam tightly against the drum to prevent such rotation, rotation in the opposite direction effectively releasing the pressure of the brake on the drum, except for the overcenter spring, thereby allowing the drum to rotate with respect thereto. Positioning the lever in the other stable position effectively reverses the operation of the mechanism, reversing the rotational directions of freewheeling and locking.
There are, of course, other applications for such devices. By way of example, conveyors are sometimes used in either of two directions, such as for both loading and unloading trucks. Frequently it would be convenient or enhance safety if the conveyor could be allowed to roll in the desired direction, but resist movement in the opposite direction, a function easily and economically accomplished with the present invention.